A propeller-driven type model airplane utilizing radio control usually has single or twin propellers provided on the airframe; it is a toy for play wherein these propellers are driven by a motor, an engine or the like, so that the toy plane can be made to fly freely in the air. Such model airplanes, whether they are single-motored or twin-motored, obtain their propulsive force from the propellers being rotated with prescribed outputs. They are so designed that the airframe can be operated in an arbitrary direction, rightward or left-ward, or upward or downward, by controlling discretely a rudder provided in a vertical tail plane and an elevator provided in a horizontal tail plane, or the like, respectively.
The propellers of the prior-art model airplanes, irrespective of whether the airplane is single-motored or twin-motored, are employed only for driving the airframe, and the elevator or the rudder is required and used for directing the airframe upward or downward, or rightward or leftward. For such model airplanes, accordingly, a control servo and a mechanical mechanism for controlling the elevator and the rudder are necessary, and thereby the structure is complicated and the weight increased. In addition, a driving source for the propellers is required to have a large output, and this all results in an increase in the cost of the toy as a whole. Moreover, in respect to such control of the elevator and the rudder, responsiveness to changes in direction and elevation for the radio controlled toy is not good, and this causes another problem that remote controlled operation of the toy plane is not easy.